Background Death rates for cardiovascular disease (CVD) in the U.S. are considerably higher among African-Americans than Whites, and rates for both groups in Mississippi are the highest in the nation. Although these rates have declined with time, declines have been smaller in African-Americans than Whites and are almost undetectable in Mississippi. African-Americans have high rates of modifiable CVD risk factors and their cardiovascular consequences, particularly for hypertension, are often more severe. Numerous explanations suggested for these disparities, including differences in socioeconomic status, access to health care, attitudes toward medical interventions, and biologic or genetic variation, do not appear fully to account for these differences. While biologic and genetic influences on disease risk may vary by race or ethnicity, they interact with and are modified by environmental variables such as cultural, psychosocial, and economic issues. Many of these modifiable issues may be best addressed by investigators familiar with the community. In 1998, NHLBI worked with the National Center for Minority Health and Health Disparities (NCMHD, previously the Office for Research on Minority Heath, ORMH) to initiate the Jackson Heart Study, building on the successful Jackson ARIC study in place since 1985. The NHLBI has direct responsibility for administering, assessing success in meeting milestones and in conducting the JHS. The NCMHD monitors progress toward milestones, ensures adequate participation by all parties and evaluates and suggests scientific directions for the JHS. The JHS was designed to identify factors related to development and progression of CVD and its risk factors and to assess roles of sociocultural factors (stress, racism, discrimination, coping strategies), hereditary factors, specific genetic variants, and gene-environment interactions in CVD in Jackson-area African-Americans. The JHS incorporates several Institutions in a collaboration by establishing a Coordinating Center at Jackson State University, an Undergraduate Training Center at Tougaloo College (both historically Black institutions), an Exam Center at the University of Mississippi and an NHLBI field site affiliated with the Jackson-area institutions. The objectives of the JHS are both scientific and operational. The primary scientific objective is to investigate genetic and environmental causes of the disproportionate burden of cardiovascular disease (CVD) in African-Americans and to learn how best to prevent these diseases. The operational objectives are to build research capabilities in minority institutions, address the critical shortage of minority investigators in epidemiology and prevention, and reduce barriers to dissemination and utilization of health information in a minority population. Recruitment of 5,500 JHS participants began in September 2000 and was completed in March 2004. Roughly 1,600 Jackson ARIC participants joined the JHS, while 1,300 participants were family members of roughly 220 cohort probands. 5,302 participants completed exams that included demographics, psychosocial inventories, medical history, anthropometry, resting and ambulatory blood pressure, phlebotomy and 24-hour urine collection, ECG, echocardiography, and pulmonary function. Preliminary data demonstrated a high prevalence of risk factors: 62% of recruited participants are hypertensive, 59% of the women and 43% of men are obese (BMI >30kg/m2), and 30% have metabolic syndrome. Exploration of the impact of clinical and subclinical measures, environmental and genetic variables on high risk factor levels will help identify unique approaches to reducing the disproportionate burden of CVD in African-Americans. Unfortunately, minority investigators are in short supply in epidemiology and have not typically been drawn to Mississippi for population-based research. A major goal of the study is to attract minority students and investigators to public health careers, as minority investigators often bring a richer appreciation of the health problems facing African-Americans and the scientific approaches needed to solve them than exclusively non-minority investigators can provide. Capacity building at minority institutions is critical to attracting and retaining minority students and investigators, and enhances the community's identification with and ownership of the study. This in turn improves the effectiveness of community outreach efforts at health promotion and disease prevention. Fully-functioning JHS Coordinating and Training Centers have developed in the past 5 years and are beginning data analysis and cohort follow-up for events. Jackson scholars in all 4 undergraduate years are actively participating in public health coursework, hands-on training within the study, and summer internships at other public health settings;9 annual summer short courses in epidemiology have involved health professionals;and high school students have participated in summer science, language, and math enrichment programs with an epidemiology and prevention focus. These students and health professionals are already bringing their unique perspectives to the study and helping to ameliorate the shortage of minority investigators in epidemiology and prevention. Community outreach efforts of the Study's Partnership for Community Awareness and Health Education provides the Jackson-area community with practical, up-to-date information on reduction of risk factors, practices of healthy lifestyles, and importance of adherence to proven risk-reducing therapies. The Partnership, which includes extensive participation by NHLBI field staff, has trained community health workers to bring these messages directly to Jackson-area residents. To date over 700 presentations at schools, churches, lay groups and health fairs have been made by JHS staff to enhance the awareness and acceptance of critical preventive health messages. Identifying unique contributors to the occurrence and complications of CVD among African-Americans is critical to translating research advances into improved health in this under-served group. Substantial declines in CVD in non-minority populations and regions outside the South have proven that such advances are possible;tailored approaches such as capacity-building, study-based training and community Outreach Health Promotion/Education are needed to bring these benefits to Jackson-area African-Americans.